Ctesibius

Mathematician, Engineer, Inventor (285 BC – 222 BC)

Ctesibius was a mathematician and engineer, founder of the Polytechnic School of Mathematics and Engineering of Alexandria. Together with Philon of Byzantium and Heron of Alexandria, he is one of the initiators of the automata as well as one of the greatest inventors of antiquity together with Archimedes.

Ctesibius worked in Alexandria during the Hellenistic era, when it was ruled by the Ptolemy dynasty. Alexandria was humanity’s greatest spiritual center at the time, which attracted scholars, mathematicians, artists, astronomers from all over the Greek world. Great minds such as Aristarchus, Conon, Apollonius of Rhodes, Apollonius of Perga, Hipparchus and Philon of Byzantium acted there. Ctesibius was part of this group of scientists who comprised the Museum of Alexandria, right next to the famous Library of Alexandria. Though not proven, Ctesibius is thought to have been the first headmaster of the Museum.

He is considered as one of the founding fathers of the automatic machines, as well as the Father of Pneumatics, the science that uses compressed air for operating machines. Ctesibius wrote the very first treatise on pneumatics and their application in pumps, but unfortunately none of his writings survive, although they are mentioned by numerous scientists such as Vitruvius, Athenaeus, Heron of Alexandria and Proclus. His writings include Pneumatica, Hypomnemata Mechanica, Velopoeetica and Memoirs.

The machines he invented were numerous. They ranged from water pumps, cranes and weapons to automatic machines, clocks and musical instruments. Below are listed some of his most notable inventions:

• The Hydraulic Clock, a marvelous automation that could operate continuously without human intervention. The machine operated with a series of containers one on top of the other, filled with water, a float and a statuette holding a pointer, which could show the exact hour and date on a rotating drum that contained a trace of hours of day and night.
• The Musical Mirror, a mirror that could be adjusted in height, produced music through mechanism of a closed vertical tube inside of which were musical pipes. The movement of the weight caused pressure to increase within the pipes thus producing the desired notes. It was used in his father’s barber shop.
• The piston force pump was a double suction force piston pump used for fluids. It was also known as siphon. It operated with the help of pivoted levers, handles, two vertical cylindrical containers and valves. The device is still used extensively to this day by firefighters, albeit in different forms.
• The Hydraulis, constructed during the 3^rd century BC was the very first keyboard instrument ever created. It used water and compressed air, the latter delivered through a series of pipes that produced music, depending on the 24 keys pressed on the keyboard. The Hydraulis is the forerunner of the church pipe organ used today. A contemporary replica of the Hydraulis survives to this day.
• Cranes that could lift very heavy objects; worked using a system of compressed water.
• Cannons that operated with compressed air and hydraulic catapults.
• Automations for entertainment, such as a singing cornucopia and a statue that stood up and sat down continuously using a cam-operated mechanism. Although a simple act, the statue produced a lot of excitement, at a time when the power of the toothed gear was being researched.

Ctesibius’ works deeply influenced the Romans and the scientists of the Renaissance. Modern day scholars have estimated that Ctesibius and the Greeks of his era were 100 years away from inventing the steam engine. Had this occurred, the Industrial Revolution would have begun almost 2000 years ago in Greece, instead of the 18^th century. Today, Ctesibius’ inventions have been recreated and most of them still in use.

Bibliography:

1. 1. Ctesibius of Alexandria. History-computer.com. Web.
   2. Georgakopoulos, Konstantinos. Ancient Greek Scientists. Georgiades: Athens, 1996. Print.
   3. Kotsanas, Kostas. Ancient Greek Technology The Inventions of the ancient Greeks. Kostas Kotsanas: Pyrgos, 2013. Print.
   4. Πώς οι αρχαίοι Έλληνες μηχανικοί έφθασαν ένα βήμα πριν από την ατμοκίνηση, χιλιάδες χρόνια πριν από την Βιομηχανική επανάσταση και την εφεύρεση της ατμοκίνητης αντλίας το 1776. Κτησίβιος, Φίλωνας και Ήρωνας ήταν οι κορυφαίοι εφευρέτες. Μηχανή του Χρόνου. Mixanitouxronou.gr. Web.